Chair

ABSTRACT

A reclining apparatus is disclosed for a chair that includes a backrest and a seat. The reclining apparatus includes a frame and a linkage installed on the frame in order to support the backrest pivotally and the seat movably so that the seat is kept substantially horizontal when the backrest is reclined.

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates to a chair and, more particular, to areclining apparatus provided between a backrest and a seat.

2. Related Prior Art

As disclosed in Taiwanese Patent Publication No. 526737, a conventionalreclining apparatus is provided between a seat and a backrest of achair. The conventional reclining apparatus includes a seat support 1,backrest support 2, an adjustment element 3, two links 4 and a lever 7.The seat support 1 is installed on a post 9 of the chair. The post 9 isa hydraulic cylinder. The backrest support 2 is pivotally connected withthe seat support 1. A backrest (marked with “B”) is installed on thebackrest support 2. The adjustment element 3 is provided in the seatsupport 1 for adjustment of the reclining of the backrest support 2relative to the seat support 1. The links 4 are provided on two sides ofthe backrest support 2. A seat (marked with “A”) is installed on thelinks 4. The lever 7 is partially inserted in the seat support 1. Whenthe lever 7 is operated, the synchronous reclining of the seat andbackrest is allowed because of the links 4 and the backrest support 2.

Some problems are encountered with the use of the conventional recliningapparatus. Firstly, the synchronous reclining of the seat and backrestentails the rising of the front edge of the seat. The front edge of theseat presses a user's legs, thus hindering the circulation of bloodthrough the legs. This causes an uncomfortable feeling for the user. Thesynchronous reclining of the seat and backrest makes the user feel liketumbling backwards. This causes the user panic.

The present invention is therefore intended to obviate or at leastalleviate the problems encountered in prior art.

SUMMARY OF INVENTION

According to the present invention, a reclining apparatus is disclosedfor a chair that includes a backrest and a seat. The reclining apparatusincludes a frame and a linkage installed on the frame in order tosupport the backrest pivotally and the seat movably so that the seat iskept substantially horizontal when the backrest is reclined.

The primary advantage of the reclining apparatus of the presentinvention is the ability to allow the reclining of the backrest whilekeeping the seat substantially horizontal.

Other advantages and novel features of the invention will become moreapparent from the following detailed description in conjunction with theattached drawings.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will be described through detailed illustration ofthe preferred embodiment referring to the drawings.

FIG. 1 is a side view of a chair equipped with a reclining apparatusaccording to the preferred embodiment of the present invention.

FIG. 2 is a perspective view of a backrest and a seat of the chairdetached from the reclining apparatus shown in FIG. 1.

FIG. 3 is an enlarged exploded view of the reclining apparatus shown inFIG. 2.

FIG. 4 is a cross-sectional view of the chair shown in FIG. 1.

FIG. 5 is a top view of the reclining apparatus shown in FIG. 4.

FIG. 6 is similar to FIG. 4 but shows the chair in a different position.

FIG. 7 is a top view of the reclining apparatus shown in FIG. 6.

FIG. 8 is similar to FIG. 1 but shows the chair in a different position.

FIG. 9 is similar to FIG. 8 but shows the chair in a different position.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring to FIG. 1, a chair includes a post 61, a backrest 62 and aseat 63. The post 61, the backrest 62 and the seat 63 are all connectedwith a reclining apparatus according to the preferred embodiment of thepresent invention. The reclining apparatus includes a frame 10, alinkage 20, an adjusting device 30 and a positioning device 40. Theframe 10 is installed on the post 61. The linkage 20 is installed on theframe 10 in order to support the backrest 62 pivotally and the seat 63movably. The adjusting device 30 is provided between the frame 10 andthe linkage 20 in order to adjust resistance against the reclining ofthe backrest 62. The positioning device 40 is provided between thebackrest 62 and the seat 63 in order to determine the position of thebackrest 62 relative to the seat 63.

Referring to FIGS. 2 and 3, the frame 10 includes a platform (notnumbered), two walls 11 formed between the platform, two tracks 12 eachformed on a related wall 11, a panel 13 formed on the platform betweenthe walls 111 and an alley 14 formed on the platform between the walls11. Each wall 11 defines an aperture 111. The tracks 12 descend to therear end from the front end of the chair. The panel 13 defines two slots131. The alley 14 is a smooth portion that ascends to the rear end fromthe front end of the chair. The platform defines aperture 15 forreceiving the post 61. A lever 16 is installed on the frame 10 andengaged with the post 61. The lever 16 is operable in order to controlthe post 61. The lever 16 and the post 61 and their interconnection arehowever conventional and will not be described in detail.

The linkage 20 includes two beams 21, a plate 26 formed between thebeams 21, a backrest support 22 connected with the plate 26, a bar 23formed between the beams 21, a connector 24 with a lower edge formedwith a loop 242 for receiving the bar 23 and an upper edge formed with ahook 241, two columns 25 each connected with a related beam 21, tworockers 52 each connected with a related column 25 and a seat support 50connected with the rockers 52.

Each beam 21 defines an aperture 211. A pin 17 is inserted in theapertures 211 and 111 in order to pivotally connect the beams 21 withthe walls 11.

The plate 26 defines a plurality of slots 201. The backrest support 22includes an upper portion connected with the backrest 62 and a lowerportion defining a plurality of slots 221. A bolt (not shown) is driventhrough each slot 201 and a related slot 221 and engaged with a nut (notshown) in order to connect the backrest support 22 with the plate 26.

Each column 25 defines an aperture 252. Each rockers 52 includes anupper portion defining an aperture 521 and a lower portion. A bolt (notshown) is driven through an aperture 252 and a related aperture 521 andengaged with a nut (not shown) in order to pivotally connect the rockers52 with the columns 25. To the bottom of the seat support 50 areattached two casters 51 for rolling on the tracks 12. Each column 25defines two apertures 251. A screw (not shown) can be driven in eachaperture 251 of each column 25 and a screw hole defined in an armrest(not shown).

The adjusting device 30 includes two leaf springs 31 provided betweenthe panel 13 and the connector 24, a fulcrum 32 for bearing variouspoints of the leaf springs 31 while sliding on the alley 14, a screw 33for moving the fulcrum 32 and a rotating element 34 for rotating thescrew 33.

Each leaf spring 31 includes a front end inserted in a related slot 131and a rear end hooked by the hook 241.

The fulcrum 32 defines a screw hole (not shown) engaged with the threadof the screw 33 so that the fulcrum 32 is moved when the screw 33 isrotated. The fulcrum 32 includes two bearing portions 321 for bearingthe leaf springs 31.

A bevel gear 331 is secured to or formed at an end of the screw 33. Therotating element 34 includes a bevel gear 341 formed at an end. Thebevel gear 341 is engaged with the bevel gear 331 so that the rotationof the rotating element 34 causes rotation of the screw 33. The rotatingelement 34 includes a crank 342 at an opposite end. The crank 342 isoperable in order to rotate the rotating element 34.

The positioning device 40 includes a rack 41 secured to the plate 26, atongue 42 for engagement with rack 41, a controlling element 43 forcontrolling the extending and retreating of the tongue 42. The rack 41defines a plurality of grooves 411 for receiving the tongue 42.

Referring to FIGS. 4 and 5, as the crank 34 is rocked, the fulcrum 32 ismoved so that the fulcrum 32 bears different positions of the leafsprings 31. The further the fulcrum 32 is moved to the rear end of thechair, the more difficult it is to recline the backrest 62,

Referring to FIGS. 6 and 7, the tongue 42 is removed from the grooves411 so that the reclining of the backrest 62 is allowed.

Referring to FIG. 8, as the backrest 62 is reclined, the seat 63 is keptsubstantially horizontal because the rockers 52 rock on the columns 25and because the casters 51 roll on the tracks 12 ascending to the rearend from the front end of the chair. However, the position of the seat63 is lowered when the backrest 62 is reclined.

Referring to FIG. 9, as a desired reclined position of the backrest 62is reached, the tongue 42 is inserted in a related groove 411. Thus, thebackrest 62 is kept in the desired reclined position.

The present invention has been described via the detailed illustrationof the preferred embodiment. Those skilled in the art can derivevariations from the preferred embodiment without departing from thescope of the present invention. Therefore, the preferred embodimentshall not limit the scope of the present invention defined in theclaims.

1. A reclining apparatus for a chair with a backrest and a seat, thereclining apparatus comprising a frame and a linkage installed on theframe in order to support the backrest pivotally and the seat movably sothat the seat is kept substantially horizontal when the backrest isreclined.
 2. The reclining apparatus according to claim 1 wherein thelinkage comprises two beams pivotally connected with the frame andconnected with the backrest, two columns connected with the beams andtwo rockers each comprising an end pivotally connected with one of thebeams and an opposite end connected with the seat.
 3. The recliningapparatus according to claim 2 wherein the linkage comprises a backrestsupport provided between the beams and the backrest.
 4. The recliningapparatus according to claim 2 wherein the linkage comprises a seatsupport connected with the rockers in order to support the seat.
 5. Thereclining apparatus according to claim 3 wherein the linkage comprisestwo casters attached to the seat support in order to roll on the frame.6. The reclining apparatus according to claim 5 wherein the framecomprises two tracks on which the casters roll.
 7. The recliningapparatus according to claim 4 wherein the tracks descends towards thebackrest.
 8. The reclining apparatus according to claim 2 wherein thelinkage comprises a plate formed between the beams and connected withthe backrest support.
 9. The reclining apparatus according to claim 8comprising a positioning device for positioning the linkage relative tothe frame.
 10. The reclining apparatus according to claim 9 wherein thepositioning device comprises a rack installed on the plate and a tonguemovably installed on the frame for engagement with rack in variouspositions.
 11. The reclining apparatus according to claim 10 wherein therack comprises a plurality of grooves for receiving the tongue.
 12. Thereclining apparatus according to claim 10 wherein the positioning devicecomprises a controlling element for controlling the extension andretreat of the tongue.
 13. The reclining apparatus according to claim 2comprising an adjusting device for adjusting the resistance against thereclining of the beams relative to the frame.
 14. The recliningapparatus according to claim 13 wherein the adjusting device comprisestwo leaf springs each with a first end connected with the frame and asecond end connected with one of the beams and a fulcrum movablyinstalled on the frame for bearing the leaf springs in variouspositions.
 15. The reclining apparatus according to claim 14 wherein theframe comprises a panel formed thereon and connected with the first endsof the leaf springs.
 16. The reclining apparatus according to claim 15wherein the panel comprises two slots for receiving the first ends ofthe leaf springs.
 17. The reclining apparatus according to claim 14wherein the adjusting device comprises a screw installed on the frameand connected with the fulcrum so that the screw can be rotated in orderto move the fulcrum.
 18. The reclining apparatus according to claim 17wherein the adjusting device comprises a rotating element installed onthe frame and connected with the screw so that the rotation of therotating element causes the rotation of the screw.
 19. The recliningapparatus according to claim 18 wherein the screw comprises a bevel gearprovided thereon, wherein the rotating element comprises a bevel gearprovided thereon and engaged with the bevel gear of the screw.
 20. Thereclining apparatus according to claim 18 wherein the rotating elementcomprises a crank provided thereon for facilitating the rotationthereof.
 21. The reclining apparatus according to claim 14 wherein thelinkage comprises a connector for connecting the beams with the secondends of the leaf springs.
 22. The reclining apparatus according to claim21 wherein the connector comprises a first edge connected with the beamsand a second edge connected with the second ends of the leaf springs.23. The reclining apparatus according to claim 22 wherein the linkagecomprises a bar provided between the beams and connected with the firstedge of the connector.
 24. The reclining apparatus according to claim 23wherein the connector comprises a loop formed on the first edge in orderto receive the bar.
 25. The reclining apparatus according to claim 22wherein the connector comprises a hook formed on the second edge inorder to hook the second ends of the leaf springs.